i don't know how much you where betting, but if i where relatively deep stacked, i would of either cbet 1/3ish of the pot to see where i was or check folded depending on the reads of the other palyer. definitely wouldn't of called the 3bet with only A high though. what kind of range did you put him on when he 3 bet you on the flop? not really a bad beat as much as it is poor play. with it being a final table though, i'm guessing you where short stacked, in which case i would of 3bet all in pre flop.